The Sydney-AAO Multi-object Integral field spectrograph


Croom, Scott M.; Lawrence, Jon S.; Bland-Hawthorn, Joss; Bryant, Julia J.; Fogarty, Lisa; Richards, Samuel; Goodwin, Michael; Farrell, Tony; Miziarski, Stan; Heald, Ron; Jones, D. Heath; Lee, Steve; Colless, Matthew; Brough, Sarah; Hopkins, Andrew M.; Bauer, Amanda E.; Birchall, Michael N.; Ellis, Simon; Horton, Anthony; Leon-Saval, Sergio; Lewis, Geraint; López-Sánchez, Á. R.; Min, Seong-Sik; Trinh, Christopher; Trowland, Holly


We demonstrate a novel technology that combines the power of the multi-object spectrograph with the spatial multiplex advantage of an integral field spectrograph (IFS). The Sydney-AAO (Australian Astronomical Observatory) Multi-object IFS (SAMI) is a prototype wide-field system at the Anglo-Australian Telescope (AAT) that allows 13 imaging fibre bundles ('hexabundles') to be deployed over a 1-degree diameter field of view. Each hexabundle comprises 61 lightly fused multi-mode fibres with reduced cladding and yields a 75 per cent filling factor. Each fibre core diameter subtends 1.6 arcsec on the sky and each hexabundle has a field of view of 15 arcsec diameter. The fibres are fed to the flexible AAOmega double-beam spectrograph, which can be used at a range of spectral resolutions ($R = \lambda/\Delta\lambda \approx 1700-13\,000$) over the optical spectrum (3700-9500 Å). We present the first spectroscopic results obtained with SAMI for a sample of galaxies at $z \approx 0.05$. We discuss the prospects of implementing hexabundles at a much higher multiplex over wider fields of view in order to carry out spatially resolved spectroscopic surveys of 10,000-100,000 galaxies.

Publication Date: 
March 2012